Yes, I repeated my opinions as expressed in an earlier post because you asked if I was saying something else.
I am of the opinion that Revenue would exercise every avenue of appeal available to it, up to and including the High Court, in the unlikely event that a decision goes against them on this point primarily because:- (a) they would be very confident of winning; and (b) the aggregate loss to the exchequer if their interpretation was found to be incorrect would be significant.
Revenue would point out that the scope of what is deductible for income tax purposes is already specified in the legislation. The fact that you have a different (and in my view incorrect) interpretation of that legislation is a different issue.
In response to a parliamentary question on 5 October 2014, the Minister for Finance stated that the reference to local authority rates in section 97(2) of the Taxes Consolidation Act 1997 is, following the removal of rates on domestic property in the late 1970's, a reference only to rates on commercial property payable to local authorities in accordance with the relevant local government legislation. Notwithstanding that local authorities can, with effect from 2015, vary the rate of LPT in accordance with section 20 of the LPT legislation, LPT is not a rate levied by a local authority and is, therefore, not deductible from gross rents under section 97(2).
The Minister went on to state that the Government has agreed in principle to accept the recommendation of the Thornhill Report that the local property tax should be a deductible expense in calculating a landlord's taxable rental income. However, as you know, the Government has yet to implement this recommendation.
The time and costs involved with any court process are always material - it is a lot more involved than simply writing a letter.
No, I am not saying that Revenue pronouncements have the same status as legislation. Revenue certainly do not make the law and cannot conclusively interpret the law - I have never suggested otherwise.